#include<stdio.h>
int main(){
	int x_;
	int y_;
	scanf("%d %d",&x_,&y_);
	int x[5];
	int y[5];
	for(int z=0;z<5;z++){
		x[z]=x_%10;
		y[z]=y_%10;
		x_=int(x_/10);
		y_=int(y_/10);
	}
	int carry=0;
	int n[5];
	int k=0; 
	for(int c=0;c<5;c++){
		if(x[c]==0&&y[c]==0&&carry==0){
			break;
		} 
		n[c]=(x[c]+y[c]+carry)%2;
		if(x[c]+y[c]+carry>=2){
			carry=1;
		}
		else{
			carry=0;
		}
		k++;
	}
	for(int u=k-1;u>=0;u--){
		printf("%d",n[u]);
	}
}
